Subject: How to make better granular activated carbon
Content: The granular activated carbon with high strength was prepared by heating wood phosphate mixture at low temperature and using tar generated during its pyrolysis as binder. In this paper, the process conditions and plasticizing mechanism of granular activated carbon prepared by phosphoric acid were studied, which provided scientific data and theoretical basis for the preparation of high strength granular activated carbon. Fir chip as the raw materials, H - POs as activator, using single factor analysis and orthogonal experimental design method, this paper discusses the influence granular activated carbon pore structure and the iodine adsorption value, methylene blue and strength of various preparation factors, determine the optimum process conditions of preparation of granular activated carbon phosphoric acid, phosphoric acid concentration is 70%, dipping 180%, kneading temperature is 170 ℃ , for 60 min kneading time, activation temperature is 350 ℃ , the activation time of 210 min. The iodine adsorption value, methylene blue adsorption value, strength and BET specific surface area of GAC were 1020.04mGG, 225mg/g, 88.73% and 1486.48m2/g respectively. The experimental results show that the impregnation ratio and carbon activation temperature have great effects on the adsorption performance of GAC, while the kneading temperature and impregnation ratio have great effects on the strength of GAC. Because the strength of GAC decreases with the increase of impregnation ratio, and the decrease range is large, so the preparation of GAC with compound activator is proposed. The results show that the composite activator can reduce the impregnation ratio of phosphoric acid to wood chips and improve the strength of granular activated carbon. coconut shell based activated carbon At the same time, the composite activator can improve the adsorption performance of GAC. Therefore, granular with good adsorption performance and high strength can be prepared by this method.